The kangaroo package

Binary parsing with random access. The target file to be
parsed is loaded into memory at the start (represented as
an IOUArray Int Word8). Parsing proceeds by moving a cursor
around, the array is left intact. This allows _jumping_
inside the file and contrasts with other parser
combinators that progress via consuming input.

* Caveat * - the above of course means that the target file
is obliged to be small enough to fit into memory.

** MAJOR CAVEAT ** - kangaroo is somewhat half-baked (maybe
now two thirds baked). The parsing machinery seems good but the
combinators need more work. It's on Hackage because I'm using
it with Hurdle which was already on Hackage and the techinique
of moving a cursor rather than consuming input seems at least
interesting.

Currently kangaroo is twinned with its own library of formatting
combinators (JoinPrint), at some point this is may go in its a
separate package.

Changelog:

0.4.0 Changed JoinPrint to have distinct types for single-line
documents (Doc) and multi-line documents (VDoc). This is
because single-line docs track their horizontal length.

Added a skip primitive to the Parse Monad. Added local and
asks to the Reader top-level modules.